Good idea BUT...
AS is a simple system - it checks nothing, it just bids as if it was you even if your snipe is less than the existing highest bid. To put in any form of checking would add an overhead and, as I suspect the majority of snipers would choose this option, it would cause all sorts of speed problems. Look at the potential for problems that bid groups causes - AS just checks to see if previous auction(s) are won/lost - with your suggestion it would need to check current situation with only a few seconds to go and react accordingly.
R2